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Discussion Starter #1
ok... no vacuum leaks... no fuel leaks... flushed gas tank... rebuilt afm... rebuilt dizzy... clean connections everywhere... and somehow... just somehow... when i go to start it.. it will catch (no higher than 700rpms, for a split second), and then dies with the starter makin a funky noise while it dies out. should i call call her time of complete death, or is there something i havent done?
 

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Still sounds like there is something wrong with the wiring. I had a similar problem with my car, in the end i found that one of the smaller wires connected to the coil had come loose and was causing similar problems. ie firing fro a split second then dying.
Try having another look near the coil for any loose connections - im guessing you have already done this, but it's worth a try.
 

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Discussion Starter #3
ok.... i cleaned them again.... and for a try, i hooked up the timing light, and just held the trigger while my little brother cranked the car, and all of them light up... so there is spark. im running out of ideas... ya know?
 

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I don't know what you have done to your car before you made this post, so bare with me.

It has been my experience as a professional technician that even supposedly new/rebuilt parts can be bad from the start. It has been the source of many headaches for me in the past, because you want to trust that your new parts are bad.

AFM check:
Attach the leads of your ohmmeter to the terminals on the connector for the harness( I forget which ones-but you can figure it out-I think it is the #1 lead and #4). Anyhow, with the leads connected move the door inside the afm with your finger slowly to full opening. The ohmmeter should measure a steady decreases in resistance from virtually none (door closed) to infinite with the door fully open.

Note: I believe on the 280z, the opening of the door will close a switch to signal your fuel pump to operate. You may want to check on this and your fuel pressure.

Ignition: It is quite possible that all your plugs will be firing, but your timing can be completely off. You description indicates this possible symptom.
It is also quite possible that you may have a short within you coil in the secondary windings. Test voltage passing through your primary coil windings by connecting the leads of your voltmeter to the pos and neg terminals of the coil. To test secondary windings, attach a sparkplug to the coil wire that goes to the the distributor cap and ground it with a 6 in 10 gauge wire to the body. The plug should brightly spark when cranking the engine. If still not sure, replace the coil with a known good one.

Check fuel injector signals using little diode test lights. Sears sells them for roughly $15. Mac and Snap-on sell improved versions for about $25.

Check engine compression in all cylinders.

Rotate engine by hand to make sure there aren't any abnormally rough spots in turning the engine except for the normal compression in the cylinders itself (I.e. sticking pistons and pistons hitting the valves (very bad).

Check fuel pressure.

Make sure cold start system is working. Remove cold-start valve from intake manifold and crank engine. It should be spraying a continuous fine mist of fuel with engine cold and no fuel with engine warm. (be careful when working with open fuel-have the injector spray the fuel into a container.

Fuel computer check.

Easiest solution is to replce with known good spare feul computer.
Otherwise grab a wiring schematic and test voltage signals leaving computer with a voltmeter to the injectors and ignition components.

One of these situations (test) should show your problem. If not, take a breather for a day or two and come back to your car with a clear state of mind and carefully recheck all your work. Taking a break from frustrating car troubles have often led me to come back to my work and discover a very minor mistake in my installation and repair that I overlooked or didn't fasten properly.

Another note: a faulty battery or battery low on charge can cause problems(however, it is doubtful in your situation).

Good luck :))
 

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Do you have a gauge on the fuel line to check the fuel pressure? They won't start with out the correct fuel pressure.
 

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Think about it. You answered your own problem in your question. When it does start for a split second, like it's susposed to, then dies. You are not getting juice to the coil after the engine starts. The problem lies in your ignition system. Of course you would get spark, checking it with a timing light when you are just turning it over. The juice is coming straight from the battery, not thru the ignition system at that point. After the engine starts, it's switched over to your ignition system. I'd prolly check the obvious first, all connections at coil area, starter area, fused links, then finally the ign switch it's self.
 

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He is right, the car will get full 12 volts at cranking, then it switches over to the ballast once started. The ballast then lowers the voltage as to not fry the coil. I would look a bit harder. Also check your water temp sensor connections,make sure they arent connected to the thermotime. Not only talking about the actual clips, but also the femal/male connectors with green wires and black near the throttle body. Fuel guage could be reading wrong also and your out of gas, fuel pump may not be supplying enough gas etc.

Make sure you have enough fuel and spark and your engine will run!
 

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I the same problem. Turns out one of the wires going to the ballast resistor had snapped inside it's rubber sheathing. So it looks like the wire was firmly connecting, but there was no real connection. THOROUGHLY check the wires going to your ballast resister.
 

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i think thats the part right above or below the ign coil...
 
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